proxying requires a public IP though. So you can have as much IPv6 in your backend as you want, the moment you want one of these machines to serve content to th

proxying requires a public IP though. So you can have as much IPv6 in your backend as you want, the moment you want one of these machines to serve content to the wider public, you will need a public v4 address. You could use name based virtual hosting in case of plain HTTP (though there are still clients around that don't send correct host headers), but if your customers use HTTPS, you'll need one public V4 address per site because SNI still can't be used reliably.